In conventional elevator refurbishing methods, a pair of counterweight guide rails are installed behind a car hoisting zone inside a hoistway so as to line up with an existing hydraulic jack. A supporting beam is installed in an upper portion of the hoistway directly above the hydraulic jack. A hoisting machine is installed on top of this supporting beam. After refurbishing, the hydraulic jack remains inside the hoistway (see Patent Literature 1 and 2, for example).